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Schäfer L, Karande R, Bühler B. Maximizing Biocatalytic Cyclohexane Hydroxylation by Modulating Cytochrome P450 Monooxygenase Expression in P. taiwanensis VLB120. Front Bioeng Biotechnol 2020; 8:140. [PMID: 32175317 PMCID: PMC7056670 DOI: 10.3389/fbioe.2020.00140] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 02/11/2020] [Indexed: 01/31/2023] Open
Abstract
Cytochrome P450 monooxygenases (Cyps) effectively catalyze the regiospecific oxyfunctionalization of inert C-H bonds under mild conditions. Due to their cofactor dependency and instability in isolated form, oxygenases are preferably applied in living microbial cells with Pseudomonas strains constituting potent host organisms for Cyps. This study presents a holistic genetic engineering approach, considering gene dosage, transcriptional, and translational levels, to engineer an effective Cyp-based whole-cell biocatalyst, building on recombinant Pseudomonas taiwanensis VLB120 for cyclohexane hydroxylation. A lac-based regulation system turned out to be favorable in terms of orthogonality to the host regulatory network and enabled a remarkable specific whole-cell activity of 34 U gCDW -1. The evaluation of different ribosomal binding sites (RBSs) revealed that a moderate translation rate was favorable in terms of the specific activity. An increase in gene dosage did only slightly elevate the hydroxylation activity, but severely impaired growth and resulted in a large fraction of inactive Cyp. Finally, the introduction of a terminator reduced leakiness. The optimized strain P. taiwanensis VLB120 pSEVA_Cyp allowed for a hydroxylation activity of 55 U gCDW -1. Applying 5 mM cyclohexane, molar conversion and biomass-specific yields of 82.5% and 2.46 mmolcyclohexanol gbiomass -1 were achieved, respectively. The strain now serves as a platform to design in vivo cascades and bioprocesses for the production of polymer building blocks such as ε-caprolactone.
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Affiliation(s)
- Lisa Schäfer
- Department of Solar Materials, Helmholtz-Centre for Environmental Research-UFZ, Leipzig, Germany
| | - Rohan Karande
- Department of Solar Materials, Helmholtz-Centre for Environmental Research-UFZ, Leipzig, Germany
| | - Bruno Bühler
- Department of Solar Materials, Helmholtz-Centre for Environmental Research-UFZ, Leipzig, Germany
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2
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Willrodt C, Gröning JAD, Nerke P, Koch R, Scholtissek A, Heine T, Schmid A, Bühler B, Tischler D. Highly Efficient Access to (
S
)‐Sulfoxides Utilizing a Promiscuous Flavoprotein Monooxygenase in a Whole‐Cell Biocatalyst Format. ChemCatChem 2020. [DOI: 10.1002/cctc.201901894] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Christian Willrodt
- Department Solar Materials Helmholtz Center for Environmental Research GmbH – UFZ Permoser Str. 15 Leipzig 04138 Germany
- Present address: BASF SE Carl-Bosch-Straße 38 Ludwigshafen am Rhein 67063 Germany
| | - Janosch A. D. Gröning
- Environmental Microbiology Group Institute of Biosciences TU Bergakademie Freiberg Leipziger Str. 29 Freiberg 09599 Germany
- Present address: Institut für Mikrobiologie Universität Stuttgart Allmandring 31 Stuttgart 70569 Germany
| | - Philipp Nerke
- Department Solar Materials Helmholtz Center for Environmental Research GmbH – UFZ Permoser Str. 15 Leipzig 04138 Germany
| | - Rainhard Koch
- Engineering and Technology Bayer AG Kaiser-Wilhelm Allee 3 Leverkusen 51373 Germany
| | - Anika Scholtissek
- Environmental Microbiology Group Institute of Biosciences TU Bergakademie Freiberg Leipziger Str. 29 Freiberg 09599 Germany
| | - Thomas Heine
- Environmental Microbiology Group Institute of Biosciences TU Bergakademie Freiberg Leipziger Str. 29 Freiberg 09599 Germany
| | - Andreas Schmid
- Department Solar Materials Helmholtz Center for Environmental Research GmbH – UFZ Permoser Str. 15 Leipzig 04138 Germany
| | - Bruno Bühler
- Department Solar Materials Helmholtz Center for Environmental Research GmbH – UFZ Permoser Str. 15 Leipzig 04138 Germany
| | - Dirk Tischler
- Environmental Microbiology Group Institute of Biosciences TU Bergakademie Freiberg Leipziger Str. 29 Freiberg 09599 Germany
- Microbial Biotechnology Ruhr University Bochum Universitätsstr. 150 Bochum 44801 Germany
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3
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Otto M, Wynands B, Drepper T, Jaeger KE, Thies S, Loeschcke A, Blank LM, Wierckx N. Targeting 16S rDNA for Stable Recombinant Gene Expression in Pseudomonas. ACS Synth Biol 2019; 8:1901-1912. [PMID: 31298831 DOI: 10.1021/acssynbio.9b00195] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Ribosomal RNA (rRNA) operons have recently been identified as promising sites for chromosomal integration of genetic elements in Pseudomonas putida, a bacterium that has gained considerable popularity as a microbial cell factory. We have developed a tool for targeted integration of recombinant genes into the rRNA operons of various Pseudomonas strains, where the native context of the rRNA clusters enables effective transcription of heterologous genes. However, a sufficient translation of foreign mRNA transcriptionally fused to rRNA required optimization of RNA secondary structures, which was achieved utilizing synthetic ribozymes and a bicistronic design. The generated tool further enabled the characterization of the six rRNA promoter units of P. putida S12 under different growth conditions. The presence of multiple, almost identical rRNA operons in Pseudomonas also allowed the integration of multiple copies of heterologous genetic elements. The integration of two expression cassettes and the resulting disruption of rRNA units only moderately affects growth rates, and the constructs were highly stable over more than 160 generations.
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Affiliation(s)
- Maike Otto
- Institute of Applied Microbiology, RWTH Aachen University, 52074 Aachen, Germany
- Institute of Bio- and Geosciences (IBG-1: Biotechnology), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Benedikt Wynands
- Institute of Applied Microbiology, RWTH Aachen University, 52074 Aachen, Germany
- Institute of Bio- and Geosciences (IBG-1: Biotechnology), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Thomas Drepper
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Karl-Erich Jaeger
- Institute of Bio- and Geosciences (IBG-1: Biotechnology), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Stephan Thies
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Anita Loeschcke
- Institute of Molecular Enzyme Technology, Heinrich Heine University Düsseldorf, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Lars M. Blank
- Institute of Applied Microbiology, RWTH Aachen University, 52074 Aachen, Germany
- Bioeconomy Science Center (BioSC), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Nick Wierckx
- Institute of Applied Microbiology, RWTH Aachen University, 52074 Aachen, Germany
- Institute of Bio- and Geosciences (IBG-1: Biotechnology), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
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4
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Volmer J, Lindmeyer M, Seipp J, Schmid A, Bühler B. Constitutively solvent‐tolerantPseudomonas taiwanensisVLB120∆C∆ttgVsupports particularly high‐styrene epoxidation activities when grown under glucose excess conditions. Biotechnol Bioeng 2019; 116:1089-1101. [DOI: 10.1002/bit.26924] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 12/17/2018] [Accepted: 01/06/2019] [Indexed: 01/08/2023]
Affiliation(s)
- Jan Volmer
- Department of Biochemical and Chemical EngineeringTU Dortmund UniversityDortmund Germany
| | - Martin Lindmeyer
- Department of Biochemical and Chemical EngineeringTU Dortmund UniversityDortmund Germany
- Department of Solar MaterialsHelmholtz Centre for Environmental Research GmbH–UFZLeipzig Germany
| | - Julia Seipp
- Department of Biochemical and Chemical EngineeringTU Dortmund UniversityDortmund Germany
| | - Andreas Schmid
- Department of Solar MaterialsHelmholtz Centre for Environmental Research GmbH–UFZLeipzig Germany
| | - Bruno Bühler
- Department of Solar MaterialsHelmholtz Centre for Environmental Research GmbH–UFZLeipzig Germany
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5
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Schmitz AC, Hartline CJ, Zhang F. Engineering Microbial Metabolite Dynamics and Heterogeneity. Biotechnol J 2017; 12. [PMID: 28901715 DOI: 10.1002/biot.201700422] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2017] [Revised: 09/06/2017] [Indexed: 11/09/2022]
Abstract
As yields for biological chemical production in microorganisms approach their theoretical maximum, metabolic engineering requires new tools, and approaches for improvements beyond what traditional strategies can achieve. Engineering metabolite dynamics and metabolite heterogeneity is necessary to achieve further improvements in product titers, productivities, and yields. Metabolite dynamics, the ensemble change in metabolite concentration over time, arise from the need for microbes to adapt their metabolism in response to the extracellular environment and are important for controlling growth and productivity in industrial fermentations. Metabolite heterogeneity, the cell-to-cell variation in a metabolite concentration in an isoclonal population, has a significant impact on ensemble productivity. Recent advances in single cell analysis enable a more complete understanding of the processes driving metabolite heterogeneity and reveal metabolic engineering targets. The authors present an overview of the mechanistic origins of metabolite dynamics and heterogeneity, why they are important, their potential effects in chemical production processes, and tools and strategies for engineering metabolite dynamics and heterogeneity. The authors emphasize that the ability to control metabolite dynamics and heterogeneity will bring new avenues of engineering to increase productivity of microbial strains.
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Affiliation(s)
- Alexander C Schmitz
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, USA
| | - Christopher J Hartline
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, USA
| | - Fuzhong Zhang
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, USA.,Division of Biological and Biomedical Sciences, and Institute of Materials Science and Engineering, Washington University in St. Louis, St. Louis, USA
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6
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Kadisch M, Willrodt C, Hillen M, Bühler B, Schmid A. Maximizing the stability of metabolic engineering-derived whole-cell biocatalysts. Biotechnol J 2017; 12. [DOI: 10.1002/biot.201600170] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 05/22/2017] [Accepted: 06/08/2017] [Indexed: 12/20/2022]
Affiliation(s)
- Marvin Kadisch
- Department Solar Materials; Helmholtz Centre for Environmental Research - UFZ; Leipzig Germany
| | - Christian Willrodt
- Department Solar Materials; Helmholtz Centre for Environmental Research - UFZ; Leipzig Germany
| | - Michael Hillen
- Department Solar Materials; Helmholtz Centre for Environmental Research - UFZ; Leipzig Germany
| | - Bruno Bühler
- Department Solar Materials; Helmholtz Centre for Environmental Research - UFZ; Leipzig Germany
| | - Andreas Schmid
- Department Solar Materials; Helmholtz Centre for Environmental Research - UFZ; Leipzig Germany
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7
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de Souza ROMA, Miranda LSM, Bornscheuer UT. A Retrosynthesis Approach for Biocatalysis in Organic Synthesis. Chemistry 2017; 23:12040-12063. [DOI: 10.1002/chem.201702235] [Citation(s) in RCA: 135] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Indexed: 11/06/2022]
Affiliation(s)
- Rodrigo O. M. A. de Souza
- Biocatalysis and Organic Synthesis Group; Federal University of Rio de Janeiro, Chemistry Institute; 21941909 Rio de Janeiro Brazil
| | - Leandro S. M. Miranda
- Biocatalysis and Organic Synthesis Group; Federal University of Rio de Janeiro, Chemistry Institute; 21941909 Rio de Janeiro Brazil
| | - Uwe T. Bornscheuer
- Dept. of Biotechnology & Enzyme Catalysis; Institute of Biochemistry; Greifswald University; Felix-Hausdorff-Str. 4 17487 Greifswald Germany
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8
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Delvigne F, Baert J, Sassi H, Fickers P, Grünberger A, Dusny C. Taking control over microbial populations: Current approaches for exploiting biological noise in bioprocesses. Biotechnol J 2017; 12. [PMID: 28544731 DOI: 10.1002/biot.201600549] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 04/10/2017] [Accepted: 04/12/2017] [Indexed: 01/19/2023]
Abstract
Phenotypic plasticity of microbial cells has attracted much attention and several research efforts have been dedicated to the description of methods aiming at characterizing phenotypic heterogeneity and its impact on microbial populations. However, different approaches have also been suggested in order to take benefit from noise in a bioprocess perspective, e.g. by increasing the robustness or productivity of a microbial population. This review is dedicated to outline these controlling methods. A common issue, that has still to be addressed, is the experimental identification and the mathematical expression of noise. Indeed, the effective interfacing of microbial physiology with external parameters that can be used for controlling physiology depends on the acquisition of reliable signals. Latest technologies, like single cell microfluidics and advanced flow cytometric approaches, enable linking physiology, noise, heterogeneity in productive microbes with environmental cues and hence allow correctly mapping and predicting biological behavior via mathematical representations. However, like in the field of electronics, signals are perpetually subjected to noise. If appropriately interpreted, this noise can give an additional insight into the behavior of the individual cells within a microbial population of interest. This review focuses on recent progress made at describing, treating and exploiting biological noise in the context of microbial populations used in various bioprocess applications.
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Affiliation(s)
- Frank Delvigne
- University of Liège, TERRA research center, Gembloux Agro-Bio Tech, Microbial Processes and Interactions (MiPI lab), Gembloux, Belgium
| | - Jonathan Baert
- University of Liège, TERRA research center, Gembloux Agro-Bio Tech, Microbial Processes and Interactions (MiPI lab), Gembloux, Belgium
| | - Hosni Sassi
- University of Liège, TERRA research center, Gembloux Agro-Bio Tech, Microbial Processes and Interactions (MiPI lab), Gembloux, Belgium
| | - Patrick Fickers
- University of Liège, TERRA research center, Gembloux Agro-Bio Tech, Microbial Processes and Interactions (MiPI lab), Gembloux, Belgium
| | - Alexander Grünberger
- Forschungszentrum Jülich GmbH, IBG-1: Biotechnology, Jülich, Germany.,Multiscale Bioengineering, Bielefeld University, Bielefeld, Germany
| | - Christian Dusny
- Department Solar Materials, Helmholtz Centre for Environmental Research (UFZ), Leipzig, Germany
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9
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Willrodt C, Halan B, Karthaus L, Rehdorf J, Julsing MK, Buehler K, Schmid A. Continuous multistep synthesis of perillic acid from limonene by catalytic biofilms under segmented flow. Biotechnol Bioeng 2016; 114:281-290. [DOI: 10.1002/bit.26071] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 07/25/2016] [Accepted: 08/01/2016] [Indexed: 02/06/2023]
Affiliation(s)
- Christian Willrodt
- Department of Solar Materials; Helmholtz Centre for Environmental Research (UFZ); Permoserstrasse 15 04318 Leipzig Germany
| | - Babu Halan
- Department of Solar Materials; Helmholtz Centre for Environmental Research (UFZ); Permoserstrasse 15 04318 Leipzig Germany
| | - Lisa Karthaus
- Department of Biochemical and Chemical Engineering; Laboratory of Chemical Biotechnology; TU Dortmund University; Dortmund Germany
| | | | - Mattijs K. Julsing
- Department of Biochemical and Chemical Engineering; Laboratory of Chemical Biotechnology; TU Dortmund University; Dortmund Germany
| | - Katja Buehler
- Department of Solar Materials; Helmholtz Centre for Environmental Research (UFZ); Permoserstrasse 15 04318 Leipzig Germany
| | - Andreas Schmid
- Department of Solar Materials; Helmholtz Centre for Environmental Research (UFZ); Permoserstrasse 15 04318 Leipzig Germany
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10
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Dusny C, Schmid A. TheMOXpromoter inHansenula polymorphais ultrasensitive to glucose-mediated carbon catabolite repression. FEMS Yeast Res 2016; 16:fow067. [DOI: 10.1093/femsyr/fow067] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/11/2016] [Indexed: 11/13/2022] Open
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11
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Weissenborn MJ, Notonier S, Lang SL, Otte KB, Herter S, Turner NJ, Flitsch SL, Hauer B. Whole-cell microtiter plate screening assay for terminal hydroxylation of fatty acids by P450s. Chem Commun (Camb) 2016; 52:6158-61. [PMID: 27074906 DOI: 10.1039/c6cc01749e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A readily available galactose oxidase (GOase) variant was used to develop a whole cell screening assay. This endpoint detection system was applied in a proof-of-concept approach by screening a focussed mutant library. This led to the discovery of the thus far most active P450 Marinobacter aquaeolei mutant catalysing the terminal hydroxylation of fatty acids.
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Affiliation(s)
- Martin J Weissenborn
- Institute of Technical Biochemistry, Universitaet Stuttgart, Allmandring 31, 70569 Stuttgart, Germany.
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12
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Zobel S, Benedetti I, Eisenbach L, de Lorenzo V, Wierckx N, Blank LM. Tn7-Based Device for Calibrated Heterologous Gene Expression in Pseudomonas putida. ACS Synth Biol 2015; 4:1341-51. [PMID: 26133359 DOI: 10.1021/acssynbio.5b00058] [Citation(s) in RCA: 123] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The soil bacterium Pseudomonas putida is increasingly attracting considerable interest as a platform for advanced metabolic engineering through synthetic biology approaches. However, genomic context, gene copy number, and transcription/translation interplay often introduce considerable uncertainty to the design of reliable genetic constructs. In this work, we have established a standardized heterologous expression device in which the promoter strength is the only variable; the remaining parameters of the flow have stable default values. To this end, we tailored a mini-Tn7 delivery transposon vector that inserts the constructs in a single genomic locus of P. putida's chromosome. This was then merged with a promoter insertion site, an unvarying translational coupler, and a downstream location for placing the gene(s) of interest under fixed assembly rules. This arrangement was exploited to benchmark a collection of synthetic promoters with low transcriptional noise in this bacterial host. Growth experiments and flow cytometry with single-copy promoter-GFP constructs revealed a robust, constitutive behavior of these promoters, whose strengths and properties could be faithfully compared. This standardized expression device significantly extends the repertoire of tools available for reliable metabolic engineering and other genetic enhancements of P. putida.
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Affiliation(s)
- Sebastian Zobel
- Institute
of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Ilaria Benedetti
- Systems
Biology Program, Centro Nacional de Biotecnologia, CSIC, C/Darwin, 3 (Campus
de Cantoblanco), Madrid 28049, Spain
| | - Lara Eisenbach
- Institute
of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Victor de Lorenzo
- Systems
Biology Program, Centro Nacional de Biotecnologia, CSIC, C/Darwin, 3 (Campus
de Cantoblanco), Madrid 28049, Spain
| | - Nick Wierckx
- Institute
of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Lars M. Blank
- Institute
of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
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13
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Lindmeyer M, Jahn M, Vorpahl C, Müller S, Schmid A, Bühler B. Variability in subpopulation formation propagates into biocatalytic variability of engineered Pseudomonas putida strains. Front Microbiol 2015; 6:1042. [PMID: 26483771 PMCID: PMC4589675 DOI: 10.3389/fmicb.2015.01042] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 09/14/2015] [Indexed: 01/01/2023] Open
Abstract
Pivotal challenges in industrial biotechnology are the identification and overcoming of cell-to-cell heterogeneity in microbial processes. While the development of subpopulations of isogenic cells in bioprocesses is well described (intra-population variability), a possible variability between genetically identical cultures growing under macroscopically identical conditions (clonal variability) is not. A high such clonal variability has been found for the recombinant expression of the styrene monooxygenase genes styAB from Pseudomonas taiwanensis VLB120 in solvent-tolerant Pseudomonas putida DOT-T1E using the alk-regulatory system from P. putida GPo1. In this study, the oxygenase subunit StyA fused to eGFP was used as readout tool to characterize the population structure in P. putida DOT-T1E regarding recombinant protein content. Flow cytometric analyses revealed that in individual cultures, at least two subpopulations with highly differing recombinant StyA-eGFP protein contents appeared (intra-population variability). Interestingly, subpopulation sizes varied from culture-to-culture correlating with the specific styrene epoxidation activity of cells derived from respective cultures (clonal variability). In addition, flow cytometric cell sorting coupled to plasmid copy number (PCN) determination revealed that detected clonal variations cannot be correlated to the PCN, but depend on the combination of the regulatory system and the host strain employed. This is, to the best of our knowledge, the first work reporting that intra-population variability (with differing protein contents in the presented case study) causes clonal variability of genetically identical cultures. Respective impacts on bioprocess reliability and performance and strategies to overcome respective reliability issues are discussed.
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Affiliation(s)
- Martin Lindmeyer
- Laboratory of Chemical Biotechnology, Department of Biochemical and Chemical Engineering, TU Dortmund University Dortmund, Germany
| | - Michael Jahn
- Helmholtz Centre for Environmental Research - UFZ, Department for Environmental Microbiology Leipzig, Germany
| | - Carsten Vorpahl
- Helmholtz Centre for Environmental Research - UFZ, Department for Environmental Microbiology Leipzig, Germany
| | - Susann Müller
- Helmholtz Centre for Environmental Research - UFZ, Department for Environmental Microbiology Leipzig, Germany
| | - Andreas Schmid
- Laboratory of Chemical Biotechnology, Department of Biochemical and Chemical Engineering, TU Dortmund University Dortmund, Germany ; Helmholtz Centre for Environmental Research - UFZ, Department of Solar Materials Leipzig, Germany
| | - Bruno Bühler
- Laboratory of Chemical Biotechnology, Department of Biochemical and Chemical Engineering, TU Dortmund University Dortmund, Germany ; Helmholtz Centre for Environmental Research - UFZ, Department of Solar Materials Leipzig, Germany
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